Guest Anonymous Posted May 29, 2001 Share Posted May 29, 2001 hey guys just had a quick question. I was just lookin around on the net about some ideas when i found a site with info on the mopar small blocks. the url is www.allpar.com/mopar/47.html and it had some info on the newest V8 made by mopar. it's only 287 CID, 3.66"B X 3.4"S but it is SOHC with 2 valves per cylinder. also it is designed after the hemi with a slight differance in the shape of the firing chamber. intsead of round it it has a flat side (think flat tire) other than that it is the same type of firing chamber. it even has the cool look of the spark plugs going straight down the middle of the valve covers. wich could help with room for headers? With it being SOHC it should rev up real nice right? fuel injected and i think it is also an all roller valve train. I could run a turbo or supercharger to make up for lack of displacement and the fact that it is on the small side as motors go should help out with keeping traction under control? what do you guys think? I should prabably still be able to hit 400+ or more with modorate boosting. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted May 29, 2001 Share Posted May 29, 2001 Yeah this is they're much heralded Mini Hemi they've been talking about. It sounds pretty neat, but of course will be pricey until the units are in the dismantlers (which could be a while, they're not even producing them yet are they?). The specs sound pretty good on it though, would make a neat Z motor if it does'nt get real wide with its accessories and SOHC valvetrain. Regards, Lone Quote Link to comment Share on other sites More sharing options...
Guest MegaShaft_2000 Posted May 29, 2001 Share Posted May 29, 2001 They should have went with DOHC, it breathes better than SOHC. Why design a new engine and use old technology? Quote Link to comment Share on other sites More sharing options...
Guest John Adkins Posted May 30, 2001 Share Posted May 30, 2001 quote: Originally posted by MegaShaft_2000: They should have went with DOHC, it breathes better than SOHC. Why design a new engine and use old technology? Probably due to cost reasons. 1 cam per head is cheaper than two This motor is also being used in SUVs and trucks where deep breathing is not really necessary for Joe Average Citizen. They will probably come out with a DOHC version for high performance applications (I hope the Charger show car gets built someday) I've heard that the bellhousing bolt pattern is the same as the the old small block mopar ... [ May 29, 2001: Message edited by: John Adkins ] Quote Link to comment Share on other sites More sharing options...
Dan Baldwin Posted November 13, 2001 Share Posted November 13, 2001 For larger displacement V-8s, I believe OHV cam-in-block architecture is ideal. A look at a Ford DOHC v-8 vs. a GM LS-1 illustrates that you can get MUCH more displacement out of a MUCH smaller engine by sticking to cam-in-block. The DOHC does breathe better at higher rpm, but not enough to make up for the displacement disadvantage. Plus, the DOHC engine has a MUCH higher c.g., and is VERY bulky and costly. Check the hoodline of a Corvette vs. a Cobra Mustang. As far as "new" vs. "old" technology, Deusenbergs had DOHC and 4-valves/cylinder way back when in the 30s. Internal combustion technology is OLD, OHV or DOHC. Would you rather have a modern aluminum 4.7 liter DOHC that revs to 8000, or a modern aluminum OHV 5.9 liter that revs to 6500? Same power potential, but the OHV engine is cheaper and has a lower c.g. No doubt DOHC wins the hp/cu. in. honors, but what about hp/engine weight (more important if you ask me)? Food for thought.... My thoughts, anyway. Quote Link to comment Share on other sites More sharing options...
jeromio Posted November 13, 2001 Share Posted November 13, 2001 I agree with Dan. It's the marketing that tells you OHC is better. I find it funny when people complain about swapping in an "old tech" pushrod engine in place of the "high tech" OHC L28. In my opinion, the 180 degree flow of the combustion chamber on the L28 is about as old tech as you can get with internal combustion. Gimme pushrods and a cross flow chamber over OHC any day. There are engineering considerations for both designs (although I'm no engineer). The pushrod motor has the energy loss thru the pushrods - one more contact point (instead of shaft to actuator (or follower) you have shaft to rod to actuator (rocker) - assuming both have lifters in there someplace), AND the extra "moving weight" of those rods, multiplied by the number of valves. That's not so great. The OHC engine has much less loss in going from rotating camshaft to linear valve movement, but will have the ineffiency associated with the large timing chain (or belt :eek , although it's just the one chain. Typically the OHC engine will have more complexity in a V engine since all the valve gear is doubled (twice the sprockets and cams) and will be much bulkier. The Pushrod engine will be more challenged with combustion chamber and intake passage design than the OHC engine. But it will be much more compact. And clever designers can come up with nice hemi chambers despite the valve actuation issues (the Ford 429 CJ had one push rod going thru the intake passage and the exhaust rocker arm was REEEEALLY long). And if you think about it, having just the one camshaft for those 16 valves is kind of nifty. Of course Honda does this with some of it's OHC 16 valve 4s too. (Contrast this with Alfa and Jag who each used to have 2 valve per cyl., DOHC engines ). Quote Link to comment Share on other sites More sharing options...
pparaska Posted November 13, 2001 Share Posted November 13, 2001 I'm obviously with you guys (Dan, jeremio). On the street, low and mid range torque is king. Heck, even in alot of racing, it's king. I don't see the need to rev past 6000 rpm, if I can get 400 hp or more easily with a pushrod V8 that's totally streetable. Let the OHC snobs have their VTEC, DOHC, etc. It's all fine and good to brag about, but I've not seen a DOHC engine that I'd want in my Z over a pushrod V8. Now if were' 100% on the road course, things change. There are alot of technology snobs out there, no matter what the field you're talking about. I have no use for such nonsense. Quote Link to comment Share on other sites More sharing options...
fl327 Posted November 14, 2001 Share Posted November 14, 2001 i run the best bang for my buck, and right now thats 5.4 OHV with the cam in the valley, and carberated, all ive done in 40,000 miles of driving and driving hard is tuneups and a valve job, and im grrrrrrrrrrrrrreat! Quote Link to comment Share on other sites More sharing options...
fl327 Posted November 14, 2001 Share Posted November 14, 2001 ps. i usually shift hard at 5600, but if im up against a close match, its 6400, and the 327 LOVES it up there.... Quote Link to comment Share on other sites More sharing options...
Guest super280z Posted November 18, 2001 Share Posted November 18, 2001 the 4.7 is a fairly good candidate from dodge. most of the magnum line-up has been pretty bad in the performance end of the spectrum. (this being my opinion from having worked with almost all of the magnum motors.) the 4.7 however has a great powerband, it dosent run out of breath in the higher rev's and hosts Dodge's better working fuel injection setup. it gets a thumbs up from me. go check out Dragtruk.com for some interesting stats. some of the stock 4.7's are beating the 5.9L R/T dakotas in the quarter right off of the showroom floor. it seems like a stroked 4.7 and a 904 would be extremely awesome in a z. Quote Link to comment Share on other sites More sharing options...
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